A5375: Optimize LNG EC

ACTG A5375: An Open-Label, Phase II Pharmacokinetic Study to Evaluate Double-Dose Levonorgestrel Emergency Contraception in Combination with Efavirenz-Based Antiretroviral Therapy or Rifampicin-Containing Anti-Tuberculosis Therapy

Treatment Category: Treatment Experienced

Study Description
This study will determine if a higher dose of levonorgestrel Emergency Contraception (LNG EC) (commonly called “Plan B” or the “Morning After Pill”) is needed to achieve high enough drug levels in girls and women who are taking medications that are known to decrease the effectiveness of this form of birth control.

Efavirenz and rifampin, two medications commonly used to treat HIV and tuberculosis (TB), are known to lower the amount of LNG in the blood when LNG is used as a daily birth control pill. Dolutegravir, which does not lower the drug levels of LNG, will be the standard (control) group to which the other groups will be compared.

Women who are receiving efavirenz will be randomized to take either the standard or double dose of LNG EC. Women on rifampin will take a double dose of LNG EC, while the control group on dolutegravir will take the standard LNG EC dose. Drug levels will be evaluated after taking one dose of LNG EC.

Why is this study being done?

  • To see if participants who take a double dose of LNG EC and are on efavirenz or rifampin have similar drug levels as women who take the standard dose.     
  • To see if a double dose of LNG EC is safe compared to the standard dose  

Who can join?

  • Females ≥16 years of age who have started menstruating
  • Not currently pregnant, within 6 weeks of delivery, or currently breastfeeding
  • Agree to use an approved non-hormonal birth control method during the study
  • Currently taking either efavirenz, dolutegravir, or rifampin
  • Have either HIV infection or an active TB infection

What do I need to do in the study?
All participants will receive one standard or double dose by mouth, depending on which medication they are currently receiving:

Efavirenz: Randomized to either the standard dose (1.5 mg) or a double dose (3 mg) of LNG EC  
Rifampin: Double dose (3 mg) of LNG EC
Dolutegravir: Standard dose (1.5 mg) of LNG EC  

At entry, participants will take their assigned standard or double dose of LNG EC and have their blood drawn nine times over about 9 hours. They will return to the clinic for blood level sampling after 24 and 48 hours, and will then be contacted by phone at weeks 1, 2, and 4.

What treatments or drugs are involved with this study?
The study treatment that will be provided through the study is levonorgestrel EC. Anti-HIV and TB medications will not be supplied through this study.  

Study Status: